To enable a liquid crystal material to pre-form regular arrangement and alignment on a surface of a glass substrate, it is required to pre-form an alignment film on the surface of the glass substrate. First, an alignment film material is applied on the surface of the glass substrate by way of printing; then, alignment processing such as optical alignment processing, voltage alignment processing or rubbing alignment processing is performed on the alignment film material so as to cause the alignment film material to be in an alignment state, thereby forming the alignment film. However, the alignment film formed by this technology may have a problem of non-uniform thickness, and thus the display quality of a display panel is influenced.